Sine, Cosine
by roqueclasique
Summary: After two months on the road together, Dean and Sam are still figuring some things out. Angst, swearing, and monster guts. The usual. PART THREE OF THE DRIVE 'VERSE.


Nadie encendía las lámparas

A/N: This is a continuation of my previous fic, I'd Drive All Night Just to Get Back Home. If you haven't read it, all you need to know is: Dean busted his leg.

***

Lake Bennett glows under the hazy, almost-full moon, stretched out under the ink-black sky like a vast, white ocean. The surface is perfectly smooth with snow, and a fresh layer falls steadily, cocooning the world in a muffled silence. Everything is still, peaceful. Empty.

"Where the fuck is this thing?" Dean asks, huffing on his chapped, red hands in an attempt to warm them. "Thought you said midnight."

Sam peers at his watch, shines his flashlight on his wrist for a moment. "It's only eleven fifty-six."

Dean groans. "You rip people's guts out, hang their frozen skin on trees, collect their eyeballs for a bedtime snack, and still feel the need to be _punctual_? Fuckin' monsters. Fuckin'… what's this thing called again?"

"Schrekenhaut."

"Yeah. Fuckin' sauerkraut."

"Schreke—" Sam starts to correct him, then freezes. "You hear that?"

Dean tugs his hat above his ears and strains to listen. He hears the high-pitched whine almost immediately, and it's getting louder. "You ready with the flare gun?" he whispers, and Sam nods. Dean tightens his grip on the sawed-off and raises it slowly to his shoulder, leans his good hip against the snow-covered boulder they've parked themselves next to.

There's a muffled growl, and a crackle of branches, and they watch as a tall silhouette breaks through a tangle of bushes at the edge of the frozen lake, about fifty feet away from where they're standing. The creature moves strangely, graceful but disjointed, and though it walks upright on two feet and is shaped like a very large person, there is absolutely nothing human-like about its presence.

Dean feels the hackles on the back of his neck raise. "Jesus," he whispers. "You say this thing used to be a man?"

"Shut up," Sam hisses. The thing pauses for a moment, tilts back a deformed head and even from fifty feet away they can hear the sound its nostrils make as it sniffs the air.

"I thought we wanted to bring him to us?" Dean hisses back.

"Oh yeah," Sam says in his normal voice.

"Hey freak!" shouts Dean, and the Schrekenhaut swings around, huge eyes glowing wide.

"One," Sam says as it lumbers towards them. "Two. Three!"

Dean lets off a blast of rocksalt as Sam shoots the flare gun, and the creature screams and raises its arms against the sudden surge of light. Dean hears the rocksalt hit its flesh, and that should be enough to down it, but it just shakes itself off and keeps going.

"What the," Sam says.

"Fuck," Dean says, and shoots again. The thing slows down a little more this time, but keeps making its determined way towards them.

"Sam," Dean barks, "we need fire, now."

Sam's fumbling in the duffle, grappling for the makeshift blowtorch Dean fashioned out of gasoline and a can of hairspray, but he's not going fast enough.

The thing is five feet away now, headed straight for Dean. He can see its mangled jaws, moonlight glinting off the wicked fangs. And Dean, his cane three feet behind him, bad leg already buckling, can't do shit about it, can't run or step back or lunge forward. He raises the shotgun and shoots one more time, buys himself another three seconds. He has one panicked moment to wonder exactly how long it takes for your entrails to be yanked from your body, and then—

He hits the ground on his bad right side in a wave of pain, and for a moment his vision's so starry he doesn't realize what happened. Then he sees Sam pinned underneath the Shrekenhaut and hears his brother's pained gasp.

Dean bites out a curse, panic coursing through him, and shuffles forward on his elbows as fast as he can until he reaches his cane, whips out the silver-coated blade concealed within.

"Hey!" he shouts, and the thing raises its head. He catches a glimpse of Sam underneath, eyes wide, blood smeared across his cheek, and he swings out with all his might.

The sword bites into flesh with a sickening thunk, and the creature screams, rolls itself off Sam and crawls towards Dean, on all fours now. Dean, fast as he can, jabs his sword again, gets the thing in the chest, straight on. And now it's just a battle of strength, Dean leaning all his might into holding the thing off, the Schrekenhaut pushing forward. The sword goes deeper into its chest but it doesn't seem to notice, and Dean thinks, Really? Is this how I'm gonna die?

Then there's a burst of light and heat, a scream like metal grating against metal, the sickening smell of charred flesh, and the Schrekenhaut explodes. All over Dean.

Dean just lies there for a moment, panting, Schrekengoo dripping over his forehead. His brother stands above him, gripping the blowtorch.

"Fuck," Dean says.

"Yeah," Sam agrees.

Dean pushes himself into an upright position, wincing. Sam comes forward to help haul him up, and only after he's put the sword back in the cane and is testing his weight with a couple painful steps does he notice that his brother is clutching his left arm close to his chest.

"Sam," Dean says, heart sinking, "you hurt?"

"It's nothing," Sam says. "A scratch. Let's just get back to the car."

The Impala's parked just a five minutes walk from the edge of the lake, but they go slow, Dean fighting to keep his footing on the unstable, slippery snow, Sam moving carefully, trying not to jar his arm. Dean knows it's not just a scratch, but he's not going to press the issue until he can sit down and shed some light on the situation. He feels guilt welling up inside him, guilt and something else. Shame.

"I'll drive," Dean says, and Sam just nods, folds himself into the passenger seat.

Dean eases himself behind the wheel with a little grunt, turns the key in the ignition and jabs the button to turn on the heat. Then he reaches up and flicks on the Impala's interior light.

Sam's shirt is soaked in blood, and Dean's heart gives a funny little jump. "Fuck, Sam," Dean says, and steps on the gas. "Did he hit anything vital? Is it just your arm?"

"I don't know," Sam says, leans his head back. "Just the arm, I think. Why didn't the rocksalt and the flare gun work?"

"Beats me," Dean says. "Fire sure did, though."

"Should have known," Sam says, voice tired. "Cousin to the Wendigo." He closes his eyes.

"Hang in there, Sam," Dean says, flooring it. "Don't go to sleep."

"I'm not concussed, Dean, it's just a cut."

"Whatever. Stay alert."

The motel is dark save for the glaring neon sign, and Dean parks as close to their room as he can.

Sam weaves his way to the door, leans on the wall while Dean fumbles the key into the lock and ushers his brother inside the overly-warm room.

"Shirt off," he orders, flicking on the overhead lights and making sure the blinds are shut. He yanks out the first aid kit, and Sam carefully shrugs out of his jacket, tries to finagle himself out of the blood-soaked t-shirt, but it's not going to happen.

"I'm going to have to cut this off of you," Dean says. "Which really sucks, cause it's my fucking shirt."

"Ugly anyway," Sam mutters, wincing as Dean slices through the fabric and peels it carefully off him.

They both suck in a little hiss of breath when they see the wound, three claw marks running from the bottom of Sam's neck down his upper arm. The chest has been grazed, shallow and bloody, but the real problem is the shoulder. The gashes are deep, really deep, and bleeding heavily.

"You need stitches," Dean says, pressing towels to the wounds.

"Yeah. No shit."

Dean tosses Sam a flask of whiskey, and Sam gulps it, tries to sit still while his brother washes the cuts with antiseptic, winces as the hydrogen peroxide sizzles.

"So, you wanna tell me what the fuck you were thinking?" Dean asks conversationally, tugging a piece of black thread through Sam's arm.

"Huh?"

"Pushing me out of the way like that. Putting yourself in the line of fire."

"You would have been ripped to shreds, Dean."

"So you volunteered yourself for the honor?" Dean folds up a piece of gauze, tapes it over the first gash. He doesn't want to be angry with Sam right now, not while his brother's hurt, and he knows it's not really Sam he's angry with at all. But that doesn't stop the cold rage coursing through him.

"You couldn't dodge him, man, what was I supposed to do?"

"Let me handle it, and not put yourself in danger, for starters."

Sam doesn't say anything, just grimaces as Dean starts stitching the second gash. Dean is quiet, concentrates on the task at hand and tries not to focus on the fact that he wouldn't even need to be stitching Sammy up if it weren't for him. Jesus, he's supposed to be protecting the kid, not the other way around. Sam's not supposed to be taking hits for him. No.

He finishes the job in silence, and Sam mumbles a thank-you.

"Sleep with it elevated," Dean says as Sam climbs into bed. "Here." He takes a pillow off his own bed, starts to prop Sam's arm up.

"I'm fine," Sam says, batting the cushion away. "You need it more than I do. Your knee—"

"Keep the damn pillow," Dean growls, voice sharp, and Sam does. Dean gives him one of his vicodin for the pain, and Sam accepts it after a moment's hesitation.

"You all right for now?" Dean asks as Sam drinks down a cup of water.

"Yeah," he says. "I'm glad we got that thing."

"Course we got it." Dean pushes himself up from the foot of Sam's bed, tries to keep the wince of pain off his face. "I'm going outside for a minute. Yell if you need anything."

"Okay," Sam says, yawns. He's pale from loss of blood, and for a second he looks ten years old again. Dean watches him for a moment, then heads outdoors.

Snow is still coming steadily down, and Dean shivers as he lights his cigarette, takes a long drag.

He fucking hates it that his little brother threw himself in front of a monster for him tonight. Hates it.

He pictures the flash of Sam's face he saw, trapped under that fucker, bleeding, bleeding for _him, _for Dean, because he didn't trust Dean to protect himself. To protect Sam.

The worst part is, Dean's not really sure what would have happened if Sam hadn't knocked him out of the way. He'd thought, for a second there, that he was about to get ripped open like a package on Christmas morning.

He shifts his weight against the cold wall of the motel room, tests his bad leg and feels pain ricochet up through his body. Jesus. He thinks of the gashes down Sam's arm again and feels sick, feels his chest constrict. He's not just not protecting Sam – he's actively hurting him. He's a fucking liability.

He finishes his cigarette too quickly and smokes another one before heading back inside to where Sam is sleeping, bandaged arm stretched out on the pillow. He looks down at his little brother, tosses an extra blanket over him even though the motel room is too warm already.

He cleans the sword hidden in his cane, then heads to the bathroom to wash the monster guts off his own face and head, contemplates taking a shower but he's just too damn tired. He'll take one in the morning.

They've started asking for handicapped rooms because they tend to be bigger and better and cleaner and cheaper, though they're invariably non-smoking, which sucks. Usually Dean greatly appreciates the bars lining the walls of the huge bathrooms, running alongside the toilet and traveling the length of the shower. It's nice not to worry about falling over when you're trying to wash your hair or take a piss.

But right now the gleaming metal rods fill him with a furious, tight feeling that sits heavy on his torso, a feeling he can't get rid of even when he's lying in bed, listening to Sam's rhythmic breath, waiting desperately for sleep to come.

***

Pain wakes Sam up early the next morning, arm pounding like it's been put through a meat grinder.

Besides pain, grief is always the first thing he feels when he awakes, whether or not he's had a nightmare; grief so strong he can taste it, can smell burning hair once more: but it's fading quicker and quicker with each passing day. Sometimes he thinks he's holding onto it on purpose, holding onto that hollow thrum in his heart where Jess now lives. He's afraid if he lets that go, he's letting her go. Again.

He sits up carefully, arm held still, close to his torso. Glances over at his brother.

Dean is still asleep, one arm thrown over his eyes, other hand fisted loosely in the sheets. His bad leg has been uncovered, blankets twisted aside, and Sam looks at it for a moment, stares like he would never dare if Dean were awake. Stares at the scars twisting up his shin, criss-crossing his knee in intricate, surgical patterns, disappearing mid-thigh under the hem of his boxers. Sam knows they continue upwards, stopping just above his hipbone.

They scare him like Dean's other scars never have.

He stands, bedsprings squeaking, and Dean's eyes flicker open almost immediately. Sam turns his gaze quickly away before Dean catches him.

"Morning," Sam says.

"How's the arm?" Dean asks, running his tongue over dry lips, leveraging himself upright in the bed.

"Still attached," Sam says, reaches for a zip-up hoodie. He's not going to be pulling anything on over his head for a while. He goes into the bathroom to brush his teeth, is careful to close the door behind him; not for himself, but to give Dean a little privacy.

It's been two months since he's been on the road with his brother, and they're still getting to know each other anew, still feeling one another out, slowly but surely. Sam's re-learning the person he thought he knew best in the world, and it's hard sometimes.

Among other things, he's learning when it's all right to offer help and when he should just sit back and shut up. Mostly it's the latter. The mornings, for instance, when Dean's pre-coffee, pre-cigarette, pre-painkillers, and his leg is so stiff he can barely climb out of bed; that's when Sam slips into the bathroom, or goes out to get coffee, finds a pretext to give his brother that time to himself, because he know Dean hates strapping on his leg brace and struggling into his jeans with his little brother watching.

He's learning, but Dean isn't. Still doesn't know how to accept the help his little brother is so eager to offer.

Sam spits toothpaste into the sink, fills a glass of water and drinks it down, peeks under the blood-stained bandages to check out his Dean's handiwork: stitches perfect, as usual. His brother would have been a kickass seamstress. He washes the water glass out, re-fills it, and takes it to his brother, who's sitting on the bed, still in his boxers and t-shirt.

Dean gives him a strange, hard-to-read look when Sam hands him the water and bites out a curt "Thanks." He takes a swig to swallow his pills and then sets it aside. "I'm going to take a shower."

"Then breakfast?" Sam asks hopefully. Being injured makes him hungry.

"Then breakfast," Dean agrees, reaches for his cane, pushes himself up from the low bed with certain degree of difficulty. Sam watches him, remembering with a twinge of guilt how he'd slammed his brother to the ground last night. Better a sore leg than missing intestines, but still, Dean had hit the earth pretty hard.

Dean gathers his clothes and his leg brace, and yeah, he's moving slow, but seems all right. He goes into the bathroom and Sam hears the water turn on a moment later.

His arm is really killing him, so he helps himself to one of the painkillers sitting on Dean's bedside table, sits back down on his bed and leans his head against the wall, closes his eyes. He feels drained, knows he lost a lot of blood last night.

Only when Dean bangs open the door to the bathroom does he realize that he'd fallen asleep for a moment.

"Hey," Dean says, hair sticking up in wet spikes. "You want me to go pick up some breakfast? You can stay here and relax?"

"Nah," Sam says. "I'm fine."

"Come on, Sam. An injury like this isn't something you should fuck with."

Sam resists the urge to point out Dean's blatant hypocrisy and just shakes his head instead. "I took one of your vicodin. I'll be all right."

Dean shrugs. "Fine. Just let me check your bandages before we go out."

Sam obligingly slides the sweatshirt off one shoulder. Dean snags the first aid kit from the night table and leans his cane up against the bed, stands over Sam to carefully unwrap the arm. He smells like cheap motel soap, fake strawberries, maybe. The underlying scent of cigarettes; he probably sneaked one out the bathroom window so he wouldn't set the smoke detector off.

"These need to be changed," Dean says, shifts his weight a little as he starts dabbing gauze with antiseptic.

"Here," Sam says, seeing his brother's wince and scooting to the side, "sit down."

"I'm fine, Sam," Dean snaps, and Sam is surprised by the venom in his brother's tone.

"Ok_ay,_" he says, knowing he sounds like a petulant child, but can't help it. "Geez."

Dean doesn't say anything, just cleans the wounds gently with a packaged sterile-wipe.

"Ow," Sam says, because he can't help it. It hurts like a bitch.

"Sorry. Don't want this shit getting infected."

"None of the research said anything about, like, venom, did it?"

"Not that I saw," Dean says, wrapping the shoulder back up. "You'll be the experiment."

Sam zips up the sweatshirt, eases himself into another one and zips that up, too, then throws a jacket over everything.

"I'm starving," he says. "Let's go."

It's stopped snowing but the sky is still overcast in white, and the parking lot hasn't been plowed. Sam watches Dean carefully, though he hasn't seen his brother slip yet, even though they spent a good part of yesterday traipsing around the slippery woods.

But a couple feet before they reach the car, Dean's cane skids on a patch of ice and he lurches forward, missteps onto his bad leg. He would have gone down if Sam hadn't grabbed him, but he bats his brother's hands away with more strength than usual, really _punches _Sam, and it kind of hurts.

"Get _off,_" he growls, and Sam backs away, hands up.

"Sorry," he says. "You okay?"

"Forgot to put on my goddamn snow tires this morning," Dean says, attempting a joke, and Sam can see that he feels bad about snapping. Gives Sam a weak, tight-lipped smile.

"You good to drive?" he asks, and Dean's face closes up again. _What? _Sam thinks, bemused. _What did I do?_

"Yeah," is all Dean says, sliding into the front seat. He turns the key but doesn't start the car yet, just punches on the heat and lights a cigarette. Sam watches as he takes a long drag, eyes half-closed, realizes that he's trying to calm himself down. But from what?

They sit in silence for a moment while Dean smokes, then he starts the engine with a sigh. Sam leans back in the seat, raises one hand to touch his cut-up shoulder, press it a little, wince. He sees Dean track his movements, face hard.

"Do you think Dad was ever even here?" Sam asks, trying to draw Dean out of the weird funk he seems to be in.

"Doubt it," Dean says. "If he'd have been here, he would have stopped that thing himself. It was just a sidenote in his journal, anyway."

"Maybe he thought it was too much for one person."

"He could have done it alone," Dean says. "_You _could have done it alone."

"No, I couldn't," Sam says, confused by Dean's harsh tone. "Neither could he."

"Well, we haven't seen any sign of him. We knew it was a long shot, anyway."

"Yeah." Sam sighs, tucks his wounded arm a little closer to his body. "Wonder if he knows we're looking for him."

"Probably." Dean grinds his cigarette out in the car's overflowing ashtray as they pull into the parking lot of the diner. "Doubt he likes it very much."

Sam climbs out of the car, realizing that his attempt to get Dean out of his bad mood has backfired; now _he's _in a bad mood, pissed off at their father all over again.

"Then why doesn't he call and tell us to stop?" Sam asks, sulkily.

"Cause we'd trace his goddamn call, Sam, come on."

"You ever think about just going after this thing ourselves? Fuck all these pointless hunts; we know Dad's on a trail, why don't we just follow it ourselves?"

"For one thing," Dean says, pulling open the diner door with a jingle of bells, "they aren't 'pointless' hunts. We're saving lives. That's not pointless. For another thing, we _are_ following Dad's trail. We're looking for him, and he's looking for this," he lowers his voice, "demon. If we want to find the demon, we gotta find Dad first. He knows shit we don't know."

"It's like being a kid all over again," Sam mutters. "Operating on a stupid need-to-know basis."

"Two please," Dean says to the waiter, a young, pimpled teenager who's snapping his gum with an attitude that impresses Dean, this early in the morning. The kid leads them to a booth in the back – they're always getting put in back booths, Dean notices, which suits them just fine – and deposits a couple handwritten menus.

"Can you smoke in here?" Dean asks, and the kid gives him a disgusted look.

"No."

Dean groans and Sam gestures to their surroundings. "This is a family place, man."

It's true. The diner's not busy, but most of the customers are families, huddled together, eating pancakes; a couple loners sit at the counter, drinking coffee.

"Goes against the fucking 5th amendment," Dean grumbles, then reaches out a hand to stop the kid, who's trying to back away. "Hey, hey, where are you going? We need coffee." He snaps his fingers at his brother. "Sam, you know what you want?"

"Raspberry pancakes," Sam says. "With bacon. Please."

"Give me an omelette, everything," Dean says. "Homefries, sausage, wheat toast, shortstack."

"Shortstack?"

"Blueberry."

The kid scribbles it down, tongue poking out of the corner of his mouth. "Got it. Be right back with your coffee."

Dean's methodically tearing his napkin into shreds, face blank in the way that means he's brooding about something.

"Quit it," Sam says, knocking his hand away from the poor napkin. "What's wrong with you, man?"

"Wrong with me?" Dean asks. "Nothin's wrong."

"Then how come you're acting like a first-grader whose mom won't let him stay up late?"

Dean scowls down at the table, rips a long strip off the reclaimed napkin.

"What is it?" Sam presses. "Your leg bothering you? You can tell me if—"

"My leg is fine," Dean bites out. "I'm not the one whose arm is sliced to ribbons."

Sam furrows his brow in confusion. "Is that what this is about? You mad at me because I got hurt?"

"Jesus, of course not. I'm mad at—" he cuts himself off, shakes his head.

"Wait," Sam says, but just then the coffee arrives.

"Thanks," Dean says, grabs the mug and chugs half of it before Sam's even sipped his.

"Dean," Sam tries. "You know it's not your fault, right? My arm?"

"Yeah, then whose fault is it?"

"Dude, _I_ jumped in front of _you, _remember? It was my choice."

"You shouldn't have to be making that kind of choice," Dean says. "If I — you shouldn't have pushed me out of the way. I could have handled it."

Sam groans. Sometimes his brother makes him feel like ripping his hair out. "You couldn't move, man!"

"Yeah," Dean says, starts shrugging his coat back on.

"Where the fuck are you going, Dean?"

"I need a cigarette."

"No, you don't, you need to talk to me."

"We're talking! That was talking!"

Sam slams his hand down on the table without thinking, bites back a yelp as the motion jars his shoulder. "Fuck," he hisses.

"Shit," Dean says, guilt written all over his face. "You okay, man? Fuck. I'm sorry."

"Dean," Sam says, incredulous. "That? Just then? That was not your fault. I slammed the table. Me. Not you."

"Yeah, but—"

"Me. Not you. Not. Your. Fault. Not your fault. Jesus, are we gonna have to re-enact Good Will Hunting here?"

"Huh?"

"Just — I don't get why you're being so weird about this. We get hurt all the time, you've said it yourself a million times, it's part of the job description. So why are you freaking out now?"

"Because it _is _my fault, Sam," Dean says, lowering himself back down to the table. "You're right. I couldn't move. I couldn't get out of the way. And because of that, I almost got you killed. You've got enough on your plate watching out for yourself, you shouldn't have to watch out for me, too."

"Why the fuck not?" Sam asks angrily. "You watch out for me all the time."

"It's different—"

"How? How is it different? I always trust you to have my back. Why don't you trust me to have yours?"

"It's not about —"

"It _is, _Dean. It _is _about trust. You want to know why I pushed you aside like that, threw myself in front of you? It's not cause I have a death wish, man; you know I'm not suicidal. It's because I trusted that you would bail me out. I wasn't worried about being killed because I knew you'd turn around and get that thing off of me, and then we'd waste it. Together. Because that's how it works. That's how it's _always _worked. And whatever – problems – whatever problems we might – Even with your leg, Dean, I'm just gonna say it cause I'm sick of dancing around it, even though, yeah, maybe you need more watching out for than you used to – even now, I trust that you're gonna be there when I need you. You needed me last night, and I was there. And then I needed you, and you were there. Get it? I know you failed math in high school, but come on, it's just an equal sign. I can't do this shit alone, and you can't either. That's why we work together, you asshole. So we can be there for each other."

Sam is breathing hard, bangs in his face, gripping his arm to his chest, and Dean just stares at him, stunned. Sometimes Sam makes speeches. Dean knows this. Yet somehow they always take him by surprise.

He clears his throat. "Dude, I did not fail math in high school. I got an A+ in calculus, so gimme some credit."

"Right," Sam says. "I forgot."

"A's in algebra and geometry."

"Oh yeah. You used to help me with my math homework."

"Cause you used to help me with my English homework." It's the closest Dean's going to come to an admission that he heard what Sam was saying, and Sam knows it, gives Dean a wide grin.

Dean gulps some coffee, sneaks a look around the diner to see if anyone was watching Sam's impassioned display. Yeah, some heads definitely swivel pretty fast to focus back on their pancakes.

The waiter shows up just then, laden down with food, and there's a blessed silence while they both focus on their breakfast.

"Pass the salt," Dean says, and Sam passes it. A moment later, Dean passes it back.

Will always pass it back.


End file.
